高水平维生素E对大鼠血脂、肝脂及肝脂质过氧化的作用

采用成年Wistar大鼠为实验动物,雌雄各半。1组为基础饲料对照组,2组为高脂饲料对照组,3、4、5组分别以维生素E30、60、120mg/d灌胃,同时喂饲高脂饲料。实验8周后停止灌胃并改饲基础饲料5周至实验结束。 研究表明:1.高水平维生素E(60和120mg/d)对高脂饲料诱导的大鼠肝实质细胞中性脂肪蓄积及肝脏(体内)脂质过氧化的增加均有明显抑制作用。2.高水平维生素E(30、60和120mg/d)无明显降低大鼠血清胆固醇、甘油三酯及增加血清高密度脂蛋白胆固醇的作用。大鼠血清维生素E与胆固醇水平呈正相关关系,与高密度脂蛋白胆固醇无明显相关。提示维生素E可能并无抑制高脂血症的作用。3.喂饲高脂饲料时雌鼠血清胆固醇的反应比雄鼠敏感,维生素E灌胃时雌鼠血清维生素E的反应比雄鼠敏感,提示存在性别差异。

EFFECTS OF HIGH LEVELS OF VITAMIN E ON SERUM AND LIVER LIPIDS AND ITS PEROXIDATION IN RATS

The mature Wistar rats were fed with high lipid diet for 8 weeks together with 3 levels (30, 60, or 120mg/day) of dl-α-tocopheryl acetate supplementation. At the end of the experiment, serum vitamin E and lipids were measured by fluorescence analysis and enzymologic method, liver crude fat was measured by Soxhlet method, liver glycogen content and fat accumulation in parenchymal cells were estimated by histo-chemical procedure and liver lipid peroxidation was evaluated by fluorescence analysis respectively. The results showed that the high lipid diet induced hypercholesterolemia and fatty liver associated with a decrease in serum high density lipoprotein cholesterol and an increase in liver peroxidation. Overall vitamin E caused no significant decrease in serum cholesterol and triglyceride levels and no significant increase in high density lipoprotein cholesterol level, except serum vitamin E level had a positive correlation with serum cholesterol level, but could inhibit the neutral fat accumulation in liver cells and liver peroxidation in rats.The levels of serum cholesterol, or the serum vitamin E and VE/CHO were higher in females than those in males significantly when dl-a-tocopheryl acetate was given to the rats fed with high lipid diet.